package com.hmall.gateway.filter;

import com.hmall.common.exception.UnauthorizedException;
import com.hmall.gateway.config.AuthProperties;
import com.hmall.gateway.util.JwtTool;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.util.AntPathMatcher;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

import java.util.List;

@Component
public class AuthGlobalFilter implements GlobalFilter, Ordered {

    private final AntPathMatcher antPathMatcher =new AntPathMatcher();

    @Autowired
    private AuthProperties authProperties;

    @Autowired
    private JwtTool jwtTool;

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

        //1、获取request
        ServerHttpRequest request = exchange.getRequest();
        //2、判断是否需要登录拦截
        if (isExclude(request.getPath().toString())){
        //放行
            return chain.filter(exchange);
        }
        //3、获取token
        String token=null;
        List<String> headers=request.getHeaders().get("authorization");
        if(headers!=null && !headers.isEmpty()){
            token=headers.get(0);
        }
        //4、校验并解析token
        Long userId=null;
        try{
            userId=jwtTool.parseToken(token);
        }catch (UnauthorizedException e){
            //拦截
            ServerHttpResponse response = exchange.getResponse();
            response.setStatusCode(HttpStatus.UNAUTHORIZED);
            return response.setComplete();
        }
        //5、传递用户信息
        String userInfo=userId.toString();
        ServerWebExchange swe=exchange.mutate()
                .request(builder -> builder.header("user-info",userInfo))
                .build();
        //6、放行
        return chain.filter(swe);
    }

    private boolean isExclude(String path){
        for (String pathPattern : authProperties.getExcludePaths()){
            if (antPathMatcher.match(pathPattern,path)){
                return true;
            }
        }
        return false;
    }

    @Override
    public int getOrder() {
        //过滤器执行顺序，值越小，优先级越高
        return 0;
    }
}
